Almost two weeks after the alleged outbreak of pneumonic plague that occurred in the Russian region of Irkutsk, in Siberia, the World Health Organization (WHO) is now trying to put together all the pieces of the puzzle to have a complete picture of whether what happened may pose any risk to the global population. The organization has published a first detailed report with all the data that the Russian authorities have provided it since the case broke out, and although it maintains that "it has not found evidence of ongoing transmission associated with this case," it immediately qualifies that there is "a key factor of uncertainty": the lack of a confirmed diagnosis in the deceased laboratory worker.
In the document, the WHO establishes a chronology of the events, in which it explains how they learned on October 2 "through media reports" of the death of an employee of the Plague Research Institute of Irkutsk (APRI) and the Far East, Daria Shipílova, 28 years old. According to what they indicate, the woman "died on October 2 after being hospitalized on September 29 for severe pneumonia."
At that time, the media reported that the so-called 'patient zero' contracted a bacteria called Yersinia pestis - which is transmitted between animals and humans - in Thailand, from where she had recently returned. Thailand's Department of Disease Control indicated that it was in contact with the WHO, but did not confirm the Russian's trip to its country.
In the following days, on October 3, 5, 6 and 7, the WHO contacted the Russian authorities to verify the information published by the media, "including the news of a possible second case" and requested additional information "to assess the possible implications for international public health", based on the International Health Regulations.
Although on October 2 the Russian consumer protection service, Rospotrebnadzor, issued a statement indicating that sanitary and epidemiological control measures had been implemented, it was not until several days later, on October 6, when the WHO received a response from the Russian Government. That message "stated that no case of plague had recently been recorded in the Irkutsk region and confirmed that an epidemiological investigation had been carried out following the identification of a case of severe pneumonia in an employee of the Irkutsk APRI."
The WHO reports that, according to the Russian authorities, "the person initially presented symptoms compatible with an acute viral respiratory infection. After testing negative for various highly dangerous pathogens, it was determined that the patient had died due to pneumonia of undetermined etiology."
Furthermore, after the death, Russia informed the WHO that "preventive and control measures had been implemented in accordance with national health legislation; as many contacts as possible were identified, subjected to medical observation and tested for high-risk pathogens."
According to the authorities of that country, until October 9, "no high-risk pathogens had been detected in any of the contacts" and there had also been no "biosafety or biological safety incidents in the institute's laboratory", so "the media reports that suggested otherwise were inaccurate."
In a second response from the Russian authorities to the WHO, it is detailed that both the patient and all her identified contacts were tested to detect viruses such as influenza, SARS-CoV-2, or other agents that cause respiratory infections and bacterial infections (such as plague and streptococcus). The results showed two cases of covid, three of rhinovirus and one of Haemophilus spp, among other minor infections.
Likewise, according to Russia, "the death was not due to a plague infection" and the victim "had been vaccinated against the high-risk pathogens with which he regularly worked." On the other hand, contrary to what had been published in the media, the deceased young researcher "had not traveled outside the Irkutsk region during the two weeks before the appearance of symptoms."
No confirmed diagnosis of death
Despite all the information provided by the Russian health authorities, the WHO insists in its report that there is a "key uncertainty factor" in this matter, and it is "the absence of a confirmed diagnosis in the deceased laboratory worker."
This organization indicates that, according to data provided by Russia, "the tests did not identify plague or other proven high-threat pathogens, and the death has been classified as pneumonia of undetermined etiology." However, the WHO "has not received information that identifies the causal agent responsible for the fatal disease," they emphasize.
Due to this lack of diagnosis, the WHO notes that "it is not in a position to independently assess whether the duration of the reported contact tracing period was sufficient to exclude all possible causes of the fatal disease."
The WHO also does not rule out that the young woman had died from an "exposure associated with the laboratory" where she worked. According to him, although the information provided by Russia did not indicate that he had been infected with proven high-threat pathogens, "the source of the deadly disease remains undetermined."
Therefore, they add, "confidence in the assessment remains limited by the absence of a confirmed etiological diagnosis and the remaining uncertainty regarding the source and mode of exposure."
In this regard, the WHO has asked Russia for "additional clinical, epidemiological and laboratory information, including confirmation of the diagnosis of the deceased laboratory worker, to improve confidence in the assessment."
